besetzt
occupied / taken
Not free because someone is currently using the seat, room, or line.
Ich wollte dich anrufen, aber dein Telefon war ständig besetzt.
I wanted to call you, but your phone was constantly busy.

occupied / taken
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occupied / taken
Not free because someone is currently using the seat, room, or line.
Ich wollte dich anrufen, aber dein Telefon war ständig besetzt.
I wanted to call you, but your phone was constantly busy.

'Besetzt' (occupied/taken) is the past participle of the verb 'besetzen' (to occupy/fill). The different meanings—a seat is occupied, a position is filled—come from the meanings of this verb.
Der Konferenzraum ist den ganzen Vormittag besetzt.
The conference room is occupied all morning.
The noun that 'besetzt' (occupied/taken) describes reveals the exact meaning. A 'besetzter Platz' (occupied seat) is not free, a 'besetzte Stelle' (filled position) has been assigned, and a 'besetztes Land' (occupied country) is under military control.
Ist dieser Platz hier noch frei oder schon besetzt?
Is this seat here still free or already taken?
In everyday life, you will hear or read 'besetzt' (occupied/busy) very often in connection with telephone lines or toilets when they are currently unavailable.
Immer wenn ich anrufe, ist die Leitung besetzt.
Every time I call, the line is busy.
When a role or job position has been filled, the preposition 'mit' (with) is often used to name the person or type of person.
Die Position wurde mit einer erfahrenen Managerin besetzt.
The position was filled with an experienced manager.
free
'frei' and 'besetzt' are opposites when someone is currently using a seat, a room, or a line. 'frei' means that you can use something. 'besetzt' means that it is not available right now. 'besetzt' is especially natural for toilets, seats, and phone lines. 'frei' fits when you are asking about an available seat or appointment.

Die Leitung ist dauernd besetzt, deshalb rufe ich später noch einmal an.
The line is constantly busy, so I'll call again later.
Ist dieser Stuhl noch frei?
Is this chair still available?